/*
 * Copyright (c) 2004-2022, University of Oslo
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 * Redistributions of source code must retain the above copyright notice, this
 * list of conditions and the following disclaimer.
 *
 * Redistributions in binary form must reproduce the above copyright notice,
 * this list of conditions and the following disclaimer in the documentation
 * and/or other materials provided with the distribution.
 * Neither the name of the HISP project nor the names of its contributors may
 * be used to endorse or promote products derived from this software without
 * specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
package org.hisp.dhis.monitoring.metrics.jdbc;

import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.List;

import javax.sql.DataSource;

/**
 * A {@link DataSourcePoolMetadataProvider} implementation that returns the
 * first {@link DataSourcePoolMetadata} that is found by one of its delegate.
 *
 * @author Stephane Nicoll
 * @since 2.0.0
 */
public class CompositeDataSourcePoolMetadataProvider implements DataSourcePoolMetadataProvider
{
    private final List<DataSourcePoolMetadataProvider> providers;

    /**
     * Create a {@link CompositeDataSourcePoolMetadataProvider} instance with an
     * initial collection of delegates to use.
     *
     * @param providers the data source pool metadata providers
     */
    public CompositeDataSourcePoolMetadataProvider( Collection<? extends DataSourcePoolMetadataProvider> providers )
    {
        this.providers = (providers != null) ? Collections.unmodifiableList( new ArrayList<>( providers ) )
            : Collections.emptyList();
    }

    @Override
    public DataSourcePoolMetadata getDataSourcePoolMetadata( DataSource dataSource )
    {
        for ( DataSourcePoolMetadataProvider provider : this.providers )
        {
            DataSourcePoolMetadata metadata = provider.getDataSourcePoolMetadata( dataSource );
            if ( metadata != null )
            {
                return metadata;
            }
        }
        return null;
    }

}